Current surface cleaning apparatus generally employs suction means. One of the drawbacks of such suction means is that the fans used to generate suction are relatively inefficient, i.e. typically 10 to 12 percent efficient in use, with the result that such apparatus tends not to be easily portable. This is especially the case where the apparatus incorporates batteries for powering the motor. It is therefore not practical to incorporate batteries of sufficient power in a readily portable suction cleaner in order to provide the degree of suction required for effective cleaning.
It is known to provide surface cleaning apparatus, such as for sweeping, in which an elongate brush arrangement, sometimes known as a brush bar, is supported for rotation in a housing which is adapted to be propelled at least in a forwards direction. The brush arrangement generally extends transversely of the housing and is adapted to contact a surface beneath it. The brush arrangement is arranged to be rotated by friction resulting from propelling the housing across a floor. The housing can be provided with wheels which contact the surface. One of the drawbacks of such a construction is that the friction drive is not very effective.
It is also known to provide one or more auxiliary brush arrangements extending outwardly from one or two front corners of the housing. The auxiliary brush arrangement is provided for rotation about an axis inclined to the vertical and is provided with radial bristles. An auxiliary brush arrangement of this kind is described in GB-A-1 547 286. The auxiliary brush arrangement is freely rotatable and relies for its rotation on contact with the floor or a skirting board of a room during propulsion of the apparatus across the floor. Such means of rotation is unreliable and results in particles of dust and/or dirt on the floor being flicked towards the elongate rotating brush assembly for collection by the apparatus. Furthermore, contact of the circular auxiliary brush arrangement with the floor or a skirting board results in bristles of the auxiliary brush arrangement which extend outwardly sideways from the housing undergoing angular rotation effectively in a backwards direction. This means that an auxiliary brush means extending outwardly from a front right hand corner of the housing, as viewed from above and behind the apparatus, would be rotated in a clockwise direction and would flick dust and or dirt around behind it in the direction of the elongate rotating brush arrangement. This is not very satisfactory.